MIC2174-1YMM Micrel Inc, MIC2174-1YMM Datasheet
MIC2174-1YMM
Specifications of MIC2174-1YMM
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MIC2174-1YMM Summary of contents
Page 1
... MOSFET from overheating. A soft-start is provided to reduce inrush current. Foldback current limit and “hiccup” mode short-circuit protection ensure FET and load protection. The MIC2174/MIC2174C is available in a 10-pin MSOP (MAX1954A-compatible) package junction temperature range from –40°C to +125°C. All support documentation can be found on Micrel’s web site at: www ...
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... Micrel, Inc. Ordering Information Part Number Voltage MIC2174-1YMM Adj. MIC2174C-1YMM Adj. Pin Configuration Pin Description Pin Number Pin Name Pin Function High-Side N-MOSFET Drain Connection (input): Power to the drain of the external high-side N- 1 HSD channel MOSFET. The HSD operating voltage range is from 3V to 40V. Input capacitors between HSD and the power ground (PGND) are required ...
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... IN pin and the BST pin. A boost capacitor of 0.1μF is connected between the 10 BST BST pin and the LX pin. Adding a small resistor in series with the boost capacitor can slow down the turn-on time of high-side N-Channel MOSFETs. September 2010 3 MIC2174/MIC2174C M9999-091310-C ...
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... HSD ) ≤ 40V 28V < V HSD 0°C ≤ T ≤ 85°C (MIC2174) J −40°C ≤ T ≤ 125°C (MIC2174 25°C (MIC2174C 0.8V (MIC2174 (MIC2174 0.8V(MIC2174C (MIC2174C (2) )............................................ 3. ....................................... 3.0V to 40V HSD ) ........................ −40°C to +125°C J MSOP (θ ) ..................................................130.5°C/W JA Continuous Power Dissipation (T (derate 5.6mW/° ...
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... MIC2174C Measured at DH 10mA SINK I = 10mA SOURCE V = 40V 5.5V,V = 45. BST V = 40V 5.5V,V = 45. BST 3V < V <5. < V <5. typical 363ns. OFF 5 MIC2174/MIC2174C Min. Typ. Max. Units 6 ms 0.3 0.225 0.375 MHz 0.27 0.202 0.338 0.1 V -0. -0.1V BST 2.1 Ω 3.3 1.8 Ω ...
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... OUTPUT CURRENT (A) Switching Frequency vs. Temperature 350 340 330 320 310 300 290 280 270 260 250 35 39 -40 - TEMPERATURE (°C) 6 MIC2174/MIC2174C 24V to 3.3V Efficiency VIN= OUTPUT CURRENT (A) Feedback Voltage vs. HSD Voltage 0.85 0.84 0.83 0.82 0.81 0.80 0.79 0.78 0.77 ...
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... Micrel, Inc. Typical Characteristics (Continued) Current Limit Threshold vs. Temperature 150 135 120 105 90 VFB=0.8V VFB= -40 - 100 TEMPERATURE (°C) September 2010 Quiescent Supply Current vs. Input Voltage 2 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0 3.5 4 4.5 120 INPUT VOLTAGE (V) 7 MIC2174/MIC2174C M9999-091310-C ...
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... Micrel, Inc. Functional Characteristics September 2010 8 MIC2174/MIC2174C M9999-091310-C ...
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... Micrel, Inc. Functional Characteristics (Continued) Short Circuit IL (5A/div) Vout (1V/div) Time 100μs/div September 2010 Vhsd=24V Vin=5V Vout=1.8V Iout=5A to short 9 MIC2174/MIC2174C M9999-091310-C ...
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... Micrel, Inc. Functional Diagram September 2010 Figure 1. MIC2174/MIC2174C Block Diagram 10 MIC2174/MIC2174C M9999-091310-C ...
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... Ts = 1/300kHz = 3.33μ not recommended to use MIC2174/MIC2174C with a OFF-time close to T increases, the internal ripple injection will increase and reduce the line regulation performance. Therefore, the maximum output voltage of the MIC2174 should be limited to 5.5V for up to 28V V higher than 28V higher output voltage is required, an adaptive on-time use the MIC2176 instead. Please refer to “ ...
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... FB compensation. The MIC2174/MIC2174C has its own stability concern; the FB voltage ripple should be in phase with the inductor current ripple and large enough to be sensed by the gm amplifier and the error comparator. The recommended FB voltage ripple is 20mV~100mV low ESR output capacitor is selected, then the FB voltage ripple may be too small to be sensed by the gm amplifier and the error comparator ...
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... Micrel, Inc. The circuit in Figure 4 illustrates the MIC2174/MIC2174C current limiting circuit. Figure 4. MIC2174/MIC2174C Current Limiting Circuit Using the typical V value of 130mV, the current limit CL value is roughly estimated as: 130mV ≈ DS(ON) For designs where the current ripple is significant compared to the load current I ...
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... C gate charge. For the low-side MOSFET: Since the current from the gate drive comes from the V the power dissipated in the MIC2174/MIC2174C due to gate drive is: A convenient figure of merit for switching MOSFETs is the on resistance times the total gate charge R ...
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... Maximizing efficiency requires both the proper selection of core material and the minimizing of winding resistance. The high frequency operation of the MIC2174/MIC2174C requires the use of ferrite materials for all but the most cost sensitive applications. Lower cost iron powder cores may be used but the increase in core loss will reduce the efficiency of the power supply ...
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... SW As described in the “Theory of Operation” subsection in Functional Description , the MIC2174/MIC2174C requires at least 20mV peak-to-peak ripple at the FB pin to make the gm amplifier and the error comparator to behavior properly. Also, the output voltage ripple should be in phase with the inductor current. Therefore, the output ...
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... C OSS1 L L STRAY1 STRAY2 Sync_buck DC Controller Figure 5. Output Parasitics is used to block DC and STRAY1 STRAY2 STRAY3 L STRAY4 Figure 6. Snubber Circuit MIC2174/MIC2174C L L STRAY3 C C OSS2 OUT L STRAY4 . A capacitor OSS OSS2 C S M9999-091310-C ...
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... FB voltage : 2 ripple is less than 20mV. If the FB voltage ripple is so small that the gm amplifier and error comparator can’t sense it, then the MIC2174/MIC2174C will lose control (29) and the output voltage will not be regulated. In order to ) have some amount of V injection method is applied for low output voltage ripple applications ...
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... FB(pp) = × div × HSD 1 = × R (R1//R2) ( inj K div MIC2174/MIC2174C and a inj 1 (37) × f × τ SW (38) must be much greater is 1nF to ff × τ (39) − D) − 1) (40) M9999-091310-C ...
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... Figure 9. The inverting input voltage V 1.2V. For applications with high V swing of V the line regulation because it is reflected back error on the FB terminal. Therefore, the maximum output voltage of MIC2174 should be limited to 5.5V for up to 28V V output voltage is required, use the MIC2176 instead. ) (41) ...
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... PCB Layout is critical to achieve reliable, stable and efficient performance. A ground plane is required to control EMI and minimize the inductance in power, signal and return paths. The following guidelines should be followed to insure proper operation of the MIC2174/MIC2174C converter. IC • The 2.2µF ceramic capacitor, which connects to the V terminal, must be located right at the IC ...
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... Micrel, Inc. Evaluation Board Schematics Figure 10. Schematic of MIC2174/MIC2174C Evaluation Board September 2010 22 MIC2174/MIC2174C M9999-091310-C ...
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... Vishay Dale 1.21Ω Resistor, Size 0603, 1% Vishay Dale 19.6kΩ Resistor, Size 0603, 1% Vishay Dale 10kΩ Resistor, Size 0603, 1% Vishay Dale 0Ω Resistor, Size 0603, 1% Vishay Dale 8.06kΩ Resistor, Size 0603, 1% (9) Micrel. Inc. 300kHz Buck Controller 23 MIC2174/MIC2174C Qty ...
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... Micrel, Inc. PCB Layout Figure 11. MIC2174/MIC2174C Evaluation Board Top Layer Figure 12. MIC2174/MIC2174C Evaluation Board Bottom Layer September 2010 24 MIC2174/MIC2174C M9999-091310-C ...
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... Micrel, Inc. PCB Layout (Continued) Figure 13. MIC2174/MIC2174C Evaluation Board Mid-Layer 1 Figure 14. MIC2174/MIC2174C Evaluation Board Mid-Layer 2 September 2010 25 MIC2174/MIC2174C M9999-091310-C ...
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... Micrel, Inc. Recommended Land Pattern September 2010 10-Pin MSOP (MM) 26 MIC2174/MIC2174C M9999-091310-C ...
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... Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully September 2010 10-Pin MSOP (MM) indemnify Micrel for any damages resulting from such use or sale. © 2010 Micrel, Incorporated. 27 MIC2174/MIC2174C http://www.micrel.com M9999-091310-C nt ...